Plaster-board.



L. M. BADER.

PLASTBB. BOARD.

APPLIoATIoN FILED FEB. e, 190s.

907,876. Patented Dec. 29, 1908.

wmwmo K f 551x f l O( I attac/nua LOUISA M. BADER, OF UPPER MONTCLAIR, NEW JERSEY.

PLAs'rEn-BQARD.

Specication of Letters Patent.

Patented Dec. 29, 1908.

Atlneaaon mea rebruary e, 190s. serial No. 414,598.

To all 'whom it ma/y concern:

Be it known that I, LOUIsA M. BADER, a citizen of the United States, residing at Upper Montclair, in the county of Essex and State of New Jersey, have invented a new and useful Plaster-Board, of which the following is a specification.

My invention relates to plaster boards, and consists of an improved form provided `with suitable means for keying the finish thereto.

In the accompanying drawings, Figure 1 is a section through my board showing it in partly finished condition. Fig. 2 is a front Viewl of a portion of my board.

Similar reference characters are employed to illustrate corresponding parts throughout the several figures of the drawings.

My board consists .of central core A composed of plaster of paris or other like plastic material adapted to harden on setting, in which is embedded fibrous material of some sort, preferably cocoa fiber for the usual purposes of strengthening the board and givin cohesiveness thereto. The board is coate exteriorlywith a sheet of paper B on each side thereof. It is obvious that any other material might be used for this coating, such as burlap, linen or the like, without aflecting this arrangement. Through the board thus formed are a series of perforations C which I have here shown in the circular form, thou h any other cross sectional form might be equally well adapted for my purpose. The object of these perforations may be readily seen by reference to Fi 1, wheretlrelpartly;

finished board shows t at the smoot coat applied to the surface forms projections extending into these perforationaas at D.

I am aware that other boards have been manufactured having a fibrous material embedded in them with paper or the like on the outrside, andI am,valso, aware that metal plates have been used for plastering with perforations therethrough, but my invention presents marked differences over these, inasmuch as the plastic material used in the body thereof is of a similar nature to the finished surface and through that material bein of likeanature, I obtain a much more per ect key, as there is not only a mechanical key vdue to the holes receiving material, but `there is, also, a mechanical key due to the ends of the fiber on the surface of the holes uniting with the finish, and there is a key obtained by the adhesion of one plastic surface to the other in t'hese holes. Y I claimz- A plaster board formed of an initially plastic material combined with loose fibrous ma-l terial'and having a plurality of bonding erforations extending therethrough, su ace material covering the opposite sides of the plastic board, coating materialcovering the surface material on one side of the board and extending through the bonding perforations, the ber being exposed at the walls or perforations, thereby to form a mechanical -bond with the coating material, the initial plastic material being also, exposed at the walls of the perforations so that it may adhere to the coating material. v

' In testimony ythat I claim the foregoing as my own, I have hereto affixed my slgnature in the presence of two witnesses.

LOUISA M. BADER.

. Witnesses: n

RoB'r. M. HENING, EDNA I. NEILL. 

